Apparatus for treating paper



Dec. 15, 1936. .R. s. BRACEWELL APPARATUS FOR TREATING PAPER Filed June 12, 1933 I INVENTOR. H0555 5. BRACEWELL ATTORNEYS.

Patented Dec. 15, 1936 UNITED STATES PATENT OFFICE APPARATUS FOR TREATING PAPER Russell S. Bracewell, South Hadley, Mass. Application June 12, 1933, Serial No. 675,352

6 Claims.

This invention relates to an apparatus for coating or coloring paper.

The principal objects of the invention are to produce coated or colored papers of greater uniformity and of generally enhanced appearance; to procure a uniform coating by spraying without subsequently brushing the coating, and to secure satisfactory light coatings by means of a spray alone; to secure economies in operation and materials; and improved working conditions. Other and further objects will be apparent from the following specification and claims.

In the accompanyingdrawing which illustrates one embodiment of the invention, T

Fig. 1 is a diagrammatic side view of a paper coating or coloring machine embodying the invention;

Fig. 2 is a side view partly in section and on a larger scale showing the color applying means;

Fig. 3 is a front view partly in section of the color applying means; and

Fig. 4 is a view similar to Fig. 2 but showing a modified form of color applying means. I

Referring to the drawing, I designates the we of paper to be coated or colored. This web is fed to the drum 2 from any suitable feed device. An endless apron 4 is trained around the drum 2 which is driven by any suitable means. This part of the device may follow the conventional construction of paper coating or color printing machines and adetailed description thereof is not necessary. Anysuitable means of presenting the paper to the coloring devices may be employed.

The color applying means comprises a casing indicated at 5. The casing comprises front and rear members designated at 6 and 1 respectively,

which are extended upwardly into close proximity to the drum 2 and serve to confine the spray of color as later described. Side members 8 con necting the members 6 and 1 form, with bottom 9, a relatively shallow reservoir for the color as indicated at I.

A roll II is mounted in the casing to take up color from the reservoir. Roll I l is' mounted on a shaft l2 journaled in suitable bearings formed in brackets l5, which are secured to frame l6 of the color machine, the brackets I also serving to support the casing 5.

The color taken up by roll II is transferred to a belt ll formed of felt or other suitable material trained around idle pulleys I9, 20, and driven pulley 2|, the shafts of which are suitably journaled on brackets 15. The shaft 22 of pulley 2| is extended beyond the frame It and is provided with a gear 23 meshing with a pinion 24 which meshes with a gear 25 carried by the shaft of cylinder 2 whereby the, belt I8 is driven in the direction of the arrows. The means for driving the shaft of drum 2 is not shown and may take 5 any suitable form. The shaft of roll I I is provided with a gear l4 meshing with a gear l3 secured to the shaft of pulley l9.

The amount of color applied to the belt 18 to be transferred to the spraying cylinder or roll 21, later described, is regulated by adoctor bar 28, extending transversely of the belt, and provided at its ends with blocks 29 slidably mounted in brackets 30 secured to the frame. The blocks 29' are threaded on rods 3| by which the doctor bar may be adjusted toward and from the belt in an obvious manner.

The spraying cylinder 21 preferably provided with a smooth surface, is carried by a shaft 32 journaled in suitable bearings 33 and the cylinder is driven in the direction of the arrow bya motor 34. The cylinder 21 is driven at a surface speed at least in excess of that obtained by rotating a 6" cylinder at 2000 revolutions per minute. The cylinder 21 operates in rubbing-contact with the belt l8 and the latter applies or rubs a'thin film of color onto the surface of the cylinder, which is traveling at a substantially higher speed than the surface of the belt. Due to the high speed of the cylinder this film is discharged against the web of paper or other material, advanced by cylinder 2, in the form of a fine uniform spray.

The arrangement of the belt is, as is clear from the drawing, such that surplus color thrown off from the roll 21 does not fall in any substantial; amount on the belt but is caught by members 6 and 1 and drains back to the reservoir.

Any suitable means may be employed to keep the color in the rcservoirproperly stirred. The means shown comprises a U-shaped blade 35, the arms 36 of which are pivoted on shaft l2 of roll II. The free upper ends of the arms are connected by links 31 to cranks 38 secured toa shaft as provided with a pulley 40 by which the shaft may be driven from any suitable source of power, not shown.

In Fig. 4 is shown a modified form of the invention in which a take-up roll Sll'and a doctor roll 5| driven in the same direction as shown by the arrows, dip into the color 52 at the bottom of casing 53. A doctor bar 54 in contact with doctor roll 5! removes the color from that roll. Roll 5| is adjusted in such proximity to take-up roll that a portion of the color taken up by 55 roll is removed by the doctor roll and a predetermined amount of color is permitted to be carried upwardly by the take-up roll. Roll 50 rotates in contact with a transfer roll 56. Roll 56 is covered with felt or the like, and operates in rubbing contact with a spraying cylinder 51 entirely similar in its construction and operation to cylinder 2'1. Baflle plates 58 prevent surplus color thrown ofi by the cylinder from falling on the take-up and transfer rolls.

I have found that by rubbing the color onto the surface of the spray roll from a belt or roll having an absorbent or wetable surface such as that provided by felt, canvas, sponge rubber or the like, the roll may be rotated at a surface speed sufficiently in excess of that obtained by rotating a 6 roll at 2000 R. P. M. to secure a fine, fog-like spray capable of uniformly depositing the color on the web, no subsequent brushing operation being necessary.

It will be understood that the term color has been used in the above specification and the following claims, in a generic sense to include the various decorating, coating and surfacing materials that it is customary to apply in liquid form to the surface of papers, fabrics or other similar materials.

It will be further understood that while I have specified a spraying roll having a surface speed above that obtained by a 6 diameter roll operated at 2000 R. P. M.- as a suitably high speed, the exact surface speed employed will depend on the physical properties of the color as to viscosity, surface tension, etc.

What I claim is:

1. A device for coating a web of paper, or the like, which comprises a casing open at the top, a cylinder rotatably mounted in the casing adjacent the open top, a reservoir for coating material positioned at the bottom of the casing, a roll positioned in the casing to take up coating material from the reservoir, means positioned intermediate the cylinder and the take-up roll adapted to receive coating material from the take-up roll and rub it onto the surface of the cylinder, and means to rotate the cylinder at a speed suflicient to discharge the material from the surface of thecylinder in a fog-like spray.

2. A device for coating a web of paper, or the like, which comprises a casing open at the top, a cylinder rotatably mounted in the casing, a series of pulleys rotatably mounted in the casing, a belt of wetable material trained around said pulleys, means to drive the belt, means to supply coating material to the belt, said cylinder being so positioned with respect to the belt that the coating material is rubbed by the belt onto the cylinder, and means to drive the cylinder at a speed sufiicient to discharge the material from the surface of the cylinder in a fog-like spray.

3. A device for coating a web of paper, or the like, which comprises a casing open at the top, a cylinder rotatably mounted in the casing adjacent the open top, a. reservoir for coating material positioned at the bottom of the casing, a roll journaled in the casing and positioned to take up coating material from the reservoir, a. belt supported in the casing and adapted to transfer the coating material from said roll to the surface of the cylinder and means to drive the cylinder at a speed sufiicient to discharge the material from the surface of the cylinder in a fog-like spray.

4. A device for coating a web of paper, or the like, which comprises a casing open at the top, a reservoir for coating material positioned at the bottom of the casing, a plurality of pulleys journaled in the casing, an endless belt formed of absorbent material trained around said pulleys, said pulleys being arranged to present a generally horizontal run of the belt adjacent the top of the casing, and side runs converging toward the bottom of the casing, a roll journaled in the casing and contacting with the belt and the coating material in the reservoir to apply coating material to the belt, a cylinder journaled in the casing adjacent its open top and positioned to receive coating material from the belt by a rubbing contact therewith and means to rotate the cylinder at a speed sufficient to discharge the material from the surface of the cylinder in a fog-like spray.

5. A device for coating a web of paper, or the like, which comprises a casing open at the top, a cylinder rotatably mounted in the casing adjacent the open top, a reservoir for coating ma terial positioned at the bottom of the casing, a roll positioned in the casing to take up coating material from the reservoir, a transfer roll provided with an absorbent surface, positioned intermediate the cylinder and the take-up roll and adapted to receive coating material from the take-up roll and apply it to the surface of the cylinder, and means to drive the cylinder at a speed suificient to discharge the material from the'surface of the cylinder in a fog-like spray.

6. A device for coating a web of paper or the like which comprises a rotatably mounted cylinder, color carrying means having a relatively absorbent surface engaging the surface of the cylinder to continuously rub color thereon, means to supply color to the color carrying means, and means to rotate the cylinder at a speed sufficient to discharge the color therefrom in the form of a fog-like spray.

RUSSELL S. BRACEWELL. 

